Question

If A1=0.5, A2=3.5 and An= ((An-1)+1)/An-2 , then A4=? a)0.4 b)2.3 c)2.9 d)9 e)9.3 0

Answer 1

Answer is (c).

Explanation:

As `A_1=0.5`, `A_2=3.5` and `A_n=(A_(n-1)+1)/A_(n-2)`

Hence `A_3=(A_(3-1)+1)/A_(3-2)=(A_2+1)/A_1=4.5/0.5=9`

and `A_4=(A_(4-1)+1)/A_(4-2)=(A_3+1)/A_2=10/3.5=20/7~=2.857`

Hence, answer is (c).